Tamperproofing is a methodology used to hinder, deter or detect unauthorised access to a device or circumvention of a security sytem.

Mechanical

Some devices contain non-standard screws or bolts in an attempt to deter access. Examples are telephone switching cabinets (which have triangular bolt heads; a hex socket would therefore fit these) and computer hard drives, which usually have a star-shaped head for the screws, known as Torx heads. Drivers for these heads are commonly available from electronics retailers.

Electrical

This style of tamperproofing is most commonly found in burglar alarms. Most trip devices (e.g. pressure pads, passive Infra_Red sensors, door switches) use 2 signal wires which, depending on the configuration of the device, are normally open or normally closed. The sensors sometimes need power too and therefore, to simplify cable runs, multi-core cable is used. Whilst 4 cores would normally be enough for the devices which do require power (leaving two spare for those which don't), cable with additional cores can be used. These additional cores can be wired into a special so-called tamper circuit in the alarm system. Burglar (or intrusion), fire and safety alarms are found in electronic form today. ... Image of a small dog taken in mid-infrared (thermal) light (false color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation. ... Reed relay and reed switches A reed switch is an electric switch that consists of a pair of ferrous metal contacts in a hermetically sealed glass envelope. ... Template:ATTENTION In electronics, a normally open switch is one that normally prevents current flow and which allows current to flow when it is perturbed. ... Template:ATTENTION In electronics, a normally closed switch is one that normally allows current to flow and which prevents current flow when it is perturbed. ... A dual-core CPU combines two independent processors and their respective caches and cache controllers onto a single silicon chip, or integrated circuit. ... A cable is two or more wires or optical fibers bound together, typically in a common protective jacket or sheath. ...

Tamper circuits are just like any other zone (in that they can be n.o. or n.c.) with the exception that the system monitors them 24 hours.

Would-be intruders run the risk of triggering the alarm by attempting to circumvent a given device.

Sensors such as movement detectors, tilt detectors, air-pressure sensors, light sensors etc. which might be employed in some burglar alarms might also be used in a bomb to hinder diffusal if discovered after being left in a imperfectly concealed location. The Massive Ordnance Air Blast (MOAB) bomb, produced in the United States. ...